1. Field of the Invention
The present invention relates to a multi-switch having a dynamic input assignment.
2. Description of the Related Art
A receiving system for satellite signals typically includes a satellite antenna including a parabolic mirror and a low-noise signal converter (LNB) and a satellite receiver. Signals emitted by a communication satellite are focused with the aid of the parabolic mirror on the LNB and received thereby. The LNB converts a part of the received signals to a predetermined intermediate frequency and provides the converted signal to the receiver. The receiver decodes from this signal those audio or video signals which are required for output of a predetermined channel.
A satellite may emit signals of different frequencies and polarization levels. A typical lower frequency band (low band) is in the range of 10.70 GHz to 11.70 GHz, a typical upper frequency band (high band) is in the frequency range of 11.70 GHz to 12.75 GHz. The signals may be polarized horizontally or vertically. Four so-called levels, on which satellite signals may be received, result by combination of these alternatives. Typical household wiring is not capable of providing sufficient bandwidth for transmitting all levels in a single cable. To provide channels from more than one of the levels simultaneously at the receiver, more cable connections are typically necessary between the satellite antenna and the receiver. A receiver may typically apply a predetermined combination of a DC voltage and a pilot frequency in the audible range at its input to activate the LNB to output signals of the assigned level.
Multi-switches, which may be introduced into the signal cable between the LNB and the receiver, have the task of distributing signals of multiple levels to one or multiple receiver(s). In some specific embodiments, a multi-switch may be integrated with the LNB.
Published German patent application document DE 20 2004 007 763 U1 describes a multi-switch having inputs and outputs for distributing satellite signals.
Published German patent application document DE 202 11 276 U1 describes a multi-switch including a programming interface, to enable an assignment of satellite signals of different polarizations and intermediate frequencies to inputs of the multi-switch.
In general, in an apartment having multiple receivers, only as many channels may be received simultaneously from different levels as cables lead from the apartment to the satellite antenna. Since the wiring from a multi-switch or LNB is always to be carried out radially, an outlay for providing additional cables may be extremely complex. To receive all analog TV channels from Astra satellites, for example, previously double wiring has been sufficient to be able to receive both levels of the low band. Since the shutdown of the analog channels, it has been important to also be able to receive the levels of the high band for the digital channels in addition to the levels of the low band. The present invention is based on the object of increasing usability of channels from different levels, without having to lay new cables.